1. Technical Field
The present invention relates to an image forming apparatus such a printer, a copying machine, and a facsimile machine, and more particularly to improvements of an image forming apparatus in which a rear-side transporting path is included as at least a portion of recording-material transporting paths.
Further, the present invention relates to a sheet feeder for use in such as a printer, a copying machine, and a facsimile machine, and more particularly to improvements of a sheet feeder of the type in which sheets are fed from the innermost recess side of a sheet tray in the inserting direction thereof, the sheet tray being disposed in such a manner as to be capable of being inserted or pulled out. The sheet used in the present invention has a size in a range of a size from a postcard to the JIS standard A3 size for a machine drawing including a legal size.
2. Related Art
As a conventional image forming apparatus of this type, one is already known which is comprised of a printer unit incorporating an image forming engine inside an apparatus body and adapted to form an image on a recording material (paper, an OHP sheet, and the like) by means of this image forming engine; a discharge tray disposed above this printer unit to discharge and accommodate the recording material for which the image formation by the printer unit is completed; a recording-material supplying unit which is disposed below the printer unit, in which a recording material cassette for accommodating the recording material is loaded in the apparatus body in such a manner as to be capable of being pulled out from a user operation side (normally, this side of the apparatus body), and in which the user operation-side surface of the recording material cassette is set substantially flush with a surface of the apparatus body; and a recording-material transporting system in which transporting paths are provided for transporting to the printer unit the recording material supplied from the recording-material supplying unit and for guiding the recording material to the discharge tray (e.g., JP-A-7-219298).
This mode is preferable in that, in terms of the shape of the image forming apparatus, it is possible to adopt a basic configuration of a box type having no external projections while the installation space of the image forming apparatus is kept to the range of the recording-material supplying unit.
Incidentally, in image forming apparatuses of this type, a recording-material transporting system of a mode which has recording-material transporting paths extending in the left-and-right direction as viewed from the user operation side is frequently adopted.
In addition, in such image forming apparatuses as compact printers, a recording-material transporting system is already present which has recording-material transporting paths extending in the back-and-forth direction as viewed from the user operation side.
Further, as a conventionally known printer, one is known which is comprised of, for example, a paper feeding tray disposed in such a manner as to be capable of being inserted or pulled out from this side of the apparatus; a paper feeding section disposed on the innermost recess side of the paper feeding tray in the inserting direction thereof and adapted to separate and feed one by one the paper accommodated in the paper feeding tray; an image forming section disposed above the paper feeding tray to form an image on the paper thus fed; and a discharge tray for discharging the paper, after being subjected to image formation, from the innermost recess side of the apparatus toward this side (refer to JP-A-11-84981).
In this type of printer, since the above-described configuration is adopted, the paper feeding passages are substantially formed in a U-shape, and the paper transporting passages are provided on the innermost recess side as viewed in the inserting direction of the paper feeding tray, i.e., on the innermost recess side of the main body of the printer.
With such a printer, since the replacement of the paper feeding tray is required in correspondence with the print size, there is a problem in that the operation becomes complicated correspondingly.
Accordingly, a printer is conventionally known in which one or a plurality of separate paper feeding units are further disposed on the lower side of the main body of the printer to make it possible to feed paper corresponding to the print size.
Here, as the paper feeding unit, one is used which has a paper feeding tray disposed in the main body of the paper feeding unit in such a manner as to be capable of being inserted or pulled out and a paper feeding section disposed on the innermost recess side of the paper feeding tray in the inserting direction thereof and adapted to separate and feed one by one the paper accommodated in the paper feeding tray. By adopting this arrangement, the paper transporting passages in the paper feeding unit can be set on the innermost recess side, so that the paper fed out from the paper feeding unit can be smoothly delivered to the main body side of the printer.
[Problems to be Solved]
However, with the image forming apparatus of the above-described mode (the mode in which the discharge tray is provided above the printer unit, and the recording-material supplying unit is provided below the printer unit), in the case where the recording-material transporting paths extending in the left-and-right direction as viewed from the user operation side are adopted, since the transporting paths are generally disposed laterally of the apparatus body in supplying the recording material in the recording-material supplying unit on the lower side to the printer unit on the upper side, if a jam of the recording material is occurred in, for instance, the lateral transporting path, the jam must be cleared after opening a side cover of the apparatus body. Thus, it is inevitable to secure a jam clearing space (a space for opening the side cover) on the side of the apparatus body.
On the other hand, with the image forming apparatus of the above-described mode, in the case where the recording-material transporting paths extending in the back-and-forth direction as viewed from the user operation side are adopted, the transporting paths are generally disposed on the user operation side (this side) of the apparatus body or on the opposite side thereof (rear side).
At this time, in the mode in which all the transporting paths are arranged on this side of the apparatus body, in a case where the recording material is jammed in the transporting path on this side, the jam can be cleared after pulling out the recording material cassette or opening the front cover of the printer unit. However, due to the limitations imposed on the transporting paths of the recording material, the degree of freedom in the configuration or layout of the image forming engine inside the printer unit is impaired.
Meanwhile, in the mode in which the rear-side transporting path is included as a portion of the transporting paths, an arrangement generally provided is such that if a jam of the recording material occurs in the rear-side transporting path, a rear cover is opened to effect the clearing of the jam. Therefore, there is a technical problem in that the installation space of the image forming apparatus must be made wider on the rear side than the area occupied by the image forming apparatus by the portion required for opening or closing the rear cover.
In addition, although a technique is proposed in which, by making use of the space from which the recording material cassette is pulled out, the recording material which is jammed in the rear-side transporting path is manually removed (JP-A-11-84981), this type of technique is premised on the fact that the recording material cassette projects from the apparatus body toward the user operation side, and that the back-and-forth dimension of the apparatus body is small. Hence, this type of technique is difficult to apply to a mode in which the recording material cassette is accommodated in the apparatus body such that the user operation-side surface of the recording material cassette becomes substantially flush with the surface of the apparatus body.
Namely, in a case where a recording material cassette is used which is capable of accommodating a recording material whose maximum size is, for instance, the JIS standard A3 size, the recording-material supplying unit must have such a back-and-forth dimension that allows at least the recording material cassette to be accommodated in the apparatus body. For this reason, when the recording material is jammed in the rear-side transporting path, even if the user, after pulling out the recording material cassette, tries to clear the jam by making use of the space from which the recording material cassette was pulled out, the user""s hand does not reach the rear-side transporting path, and the clearing of the jam is extremely difficult.
Further, with the above-described paper feeding unit, paper jams can occur during the transport of the paper. As a technique for clearing such a paper jam, one is known in which an openable door which also serves as a paper transporting chute is provided on the innermost recess side of the main body of the paper feeding unit, and as this door is opened, the jammed paper can be removed (refer to JP-A-11-84981).
However, in a case where such a technique is adopted, in view of the occurrence of the paper jam, a space where the door can be opened and a space for allowing an access by an operator must be secured on the rear side of the paper feeding unit, i.e., on the rear side of the printer. Therefore, there has been a technical problem in that a substantial occupying area becomes large correspondingly, so that the space efficiency declines.
The invention is devised to overcome the above-described technical problems, and its object is to provide an image forming apparatus requiring only a small installation area without securing a wasteful space for clearing a jam.
Further, the invention has been devised to overcome the above-described technical problems, and its object is to provide a sheet feeder capable of easily removing the jammed sheet without causing a decline in the substantial space efficiency.
[Means for Solving the Problems]
Namely, in accordance with the invention, as shown in FIG. 1, there is provided an image forming apparatus comprising: an image forming section 1 incorporating an image forming engine 2 inside an apparatus body and adapted to form an image on a recording material by means of this image forming engine 2; a recording-material discharging section 3 disposed above this image forming section 1 to discharge and accommodate the recording material for which the image formation by the image forming section 1 is completed; a recording-material supplying section 4 which is disposed below the image forming section 1, in which a recording material cassette 5 for accommodating the recording material is loaded in the apparatus body in such a manner as to be capable of being pulled out from a user operation side, and in which a user operation-side surface of the recording material cassette 5 is set substantially flush with a surface of the apparatus body; and a recording-material transporting system 6 in which transporting paths are provided for transporting to the image forming section 1 the recording material supplied from the recording-material supplying section 4 and for subsequently guiding the recording material to the recording-material discharging section, and in which a portion of the transporting path leading to the image forming section is arranged on a rear side of the apparatus body located on an opposite side to the user operation side, wherein at least either one of the recording-material supplying section 4 and the recording-material transporting system 6 is provided with a jam clearing section 8 (e.g., 8a, 8b, and 8c) for allowing the recording material jammed in a rear-side transporting path 7 to be cleared on the user operation side.
In this technical means, the terms xe2x80x9cimage forming section 1xe2x80x9d and xe2x80x9crecording-material supplying section 4xe2x80x9d in terms of their concepts respectively include the apparatus body (housing body), and both of these elements may be formed into units, or may be provided in a single apparatus body without being formed into units.
Incidentally, it goes without saying that the image forming section 1 may be provided with a recording-material supplying section such as a recording material tray 1a or a manual feeding tray 1b. 
In addition, the recording-material supplying section 4 has as its object one in which the user operation-side surface of the recording material cassette 5 is substantially flush with the surface of the apparatus body, and does not include a mode in which the recording material cassette 5 projects from the apparatus body toward this side, and the recording material which jammed in the recording-material transporting system 6 arranged on the rear side of the apparatus body can therefore be easily removed manually.
In addition, the recording material cassette 5 referred to herein includes a mode in which the recording material cassette 5 is pulled out in a state in which it is not completely disengaged from the apparatus body or a mode in which the recording material cassette 5 is pulled out in a state in which it is completely disengaged from the apparatus body, insofar as the recording material cassette 5 can be loaded in the apparatus body in such a manner as to be capable of being pulled out.
Further, the recording-material transporting system 6 is sufficient if the rear-side transporting path 7 is provided in at least a portion of the transporting paths, and the mode in which the rear-side transporting path 7 is not provided is not included in the recording-material transporting system 6.
Furthermore, the jam clearing section 8 is sufficient if it allows the recording material which jammed in the rear-side transporting path 7 to be cleared on the user operation side, and it suffices if the jam clearing section 8 is provided in at least either one of the recording-material supplying section 4 and the recording-material transporting system 6.
Here, as the place where the jam clearing section 8 is provided, it is possible to cite a portion of the rear-side transporting path 7 where a jam is likely to occur, e.g., a portion where the transporting path is bent or an inlet portion of transporting members such as a pair of rolls.
In addition, as a typical mode of the jam clearing section 8 (8a) provided in the recording-material supplying section 4, it is possible to cite an arrangement in which, as shown in FIG. 1, in a mode in which the transporting path located immediately after the recording-material supplying section 4 is the rear-side transporting path 7, the recording material cassette 5 has a recording-material accommodating portion 5a for accommodating the recording material and a recording-material transporting portion 5b disposed on an innermost recess side of the recording-material accommodating portion 5a, and the jam clearing section 8a causes the recording-material transporting portion 5b to be exposed to an outside with the recording material nipped and held in the recording-material transporting portion 5b when the recording material cassette 5 is pulled out.
In this mode, the recording-material supplying section 4 preferably has a temporary stop mechanism for temporarily stopping the recording material cassette 5 when the recording material cassette 5 is pulled out to a position where the entire recording-material accommodating portion 5a is exposed to the outside, and as the temporary stop mechanism is unlatched, the recording material cassette 5 can be further pulled out.
According to this mode, the operation of loading the recording material and the operation of clearing a jam can be handled separately, and the excessive pulling out of the recording material cassette 5 during the operation of loading the recording material can be effectively prevented.
Further, to permit the clearing of a jam in the recording-material transporting system 6, it suffices if the recording-material transporting system 6 has an intermediate transport section 10 for constituting a portion of the rear-side transporting path, and the jam clearing section 8 (e.g., 8b) is provided in the intermediate transport section 10.
The intermediate transport section 10 is sufficient if it includes a portion of the rear-side transporting path. Although the arrangement of the rear-side transporting path 7 is not particularly restricted, the intermediate transport section 10 is preferably provided in a portion of the rear-side transporting path 7 where the clearing of a jam is likely to occur.
For example, in a mode in which the transporting paths for transporting to the image forming section 1 the recording material supplied from the recording-material supplying section 4 and for subsequently guiding the recording material to the recording-material discharging section 3 has a vertically transporting path which is offset in a back-and-forth direction as viewed from the user operation side, it suffices if the recording-material transporting system 6 has the intermediate transport section 10 in which a horizontally transporting path connecting mutually offset vertically transporting paths is disposed, and the jam clearing section 8 (8b) is provided in the intermediate transport section 10.
Further, as a typical mode of the jam clearing section 8 (8b) of the intermediate transport section 10, it is possible to cite an arrangement in which the jam clearing section 8 is arranged such that a recording-material transporting portion is provided on an innermost recess side of the intermediate transport section 10, the intermediate transport section 10 is made capable of being pulled out of the apparatus body from the user operation side, and the jam clearing section 8 (8b) causes the recording-material transporting portion to be exposed to an outside with the recording material nipped and held in the recording-material transporting portion when the intermediate transport section 10 is pulled out.
In addition, as a typical mode of the jam clearing section 8 (8c) of the recording-material transporting system 6, it is possible to cite an arrangement in which, for example, in a mode in which a detachable image forming engine 2 is disposed in the apparatus body, the jam clearing section 8 (8c) is arranged such that an openable cover 11 which can be opened or closed from the user operation side is provided on the apparatus body making up a part of the image forming section 1, and after the openable cover 11 is opened and the image forming engine 2 is detached, the recording material which jammed in the transporting path leading from the image forming section 1 to the recording-material discharging section 3 is cleared by making use of a space for detaching the image forming engine 2.
Here, although the openable cover 11 is provided on the apparatus body which makes up a part of the image forming section 1, the openable cover 11 may be provided at an arbitrary portion (on an upper portion or this side of the apparatus body portion of the image forming section 1) insofar as the jam can be cleared from the user operation side.
In this case, in the mode in which the openable cover 11 is provided on the upper portion of the apparatus body portion of the image forming section 1, it is preferable to adopt a mode in which the recording-material discharging section 3 is formed integrally on top of the apparatus body portion of the image forming section, and the recording-material discharging section 3 is provided with the openable cover 11.
However, in a case where the image forming section 1 and the recording-material discharging section 3 are formed as separate units, it suffices if the recording-material discharging section 3 is also provided with an openable cover which is separate from the openable cover 11 on the image forming section 1 side.
In addition, in the invention, in view of the appearance and the operational feature of the image forming apparatus, the image forming section 1 and the recording-material supplying section 4 are preferably formed such that their respective apparatus body portions located on the user operation side are made substantially flush.
In this case, for instance, in a mode in which an apparatus body portion of the image forming section 1 has an occupying area smaller than that of an apparatus body portion of the recording-material supplying section 4, to arrange the appearance of the image forming apparatus, it suffices if a dummy cover 12 is disposed on the user operation side or the rear side of the image forming section 1, such that an area occupied by the apparatus body portion of the image forming section 1 and the dummy cover 12 is substantially equal to the occupying area of the apparatus body portion of the recording-material supplying section 4.
Further, in the invention, to permit two-side image formation in the image forming section 1, the image forming section may have a recording-material-two-side transporting section (not shown) allowing formation of images on both sides of the recording material by the image forming engine 1.
Further, as a mode which further develops the invention, in a case where an image reading section 14 of an original fixed type is incorporated, it suffices if, as shown in FIG. 1, the image reading section 14 is provided which is disposed above the recording-material discharging section 3 with at least a space provided therebetween, the space being open on the user operation side, the image reading section 14 having an original placing table on which an original is fixed, so as to read an image of the original.
In this mode, in a mode in which the recording-material discharging section 3 is formed integrally on top of an apparatus body portion of the image forming section 1, and the recording-material discharging section 3 is provided with an openable cover 11 for attaching or detaching the image forming engine, the image reading section 14 is preferably disposed movably (rotatably or vertically movably) in a space above the recording-material discharging section 3 so as to make the space above the recording-material discharging section 3 more open.
In addition, from the viewpoint of arranging the appearance of the image forming apparatus, the image reading section 14, the image forming section 1, and the recording-material supplying section 4 are formed such that their respective apparatus body portions located on the user operation side are made substantially flush.
In this case, it goes without saying that a dummy cover or the like may be used, as required.
Further, in accordance with the invention, as shown in FIG. 25A, there is provided a sheet feeder characterized by comprising: a sheet tray 802 for accommodating sheets of paper S and disposed in such a manner as to be capable of being inserted or pulled out from the operation side of an apparatus body 801; and sheet feeding member 803 disposed on an innermost recess side of the sheet tray 802 in an inserting direction thereof so as to feed out the sheet S in the sheet tray 802, wherein there is provided an interlocking mechanism 804 for moving the sheet feeding member 803 in the same direction as that of the sheet tray 802 in interlocking relation to the sheet tray 802.
In the above-described technical means, the invention of this application has as its objects not only a sheet feeder used as an external unit for an image forming apparatus such as a printer but also a sheet feeder incorporated in the main body of the image forming apparatus.
In addition, the sheet feeding member 803 has the function of feeding out the sheet S and includes, for instance, a paying-out member for paying out the sheet S on the sheet tray 801, a transporting member for transporting the sheet S paid out, a guide member for forming the transporting passage of the sheet S being transported, and the like.
Further, as for the interlocking mechanism 804, insofar as it moves the sheet feeding member 803 in the same direction as that of the sheet tray 802 in interlocking relation to the sheet tray 802, a mode in which the sheet tray and the sheet feeding member are directly connected, a mode in which they are indirectly connected by means of a sliding member or the like, and other modes may be selected, as required.
Here, from the viewpoint of facilitating the loading of sheets in the sheet tray 802, it is preferable to avoid a situation in which the sheet feeding member 803 covers the sheet tray 802 pulled out of the apparatus body 801. From this viewpoint, the interlocking mechanism 804 should preferably be arranged such that, as shown in FIGS. 25A to 25C, the sheet feeding member 803 is moved so as to offset a relative positional relationship in a moving direction between the sheet tray 802 and the sheet feeding member 803.
Further, at the time of the loading of sheets, i.e., when only the sheet tray 802 is pulled out of the apparatus body, the interlocking mechanism 804 may be moved together with the sheet feeding member 803 as shown in FIG. 25B, or may be held at its initial position without being moved together with the sheet feeding member as shown in FIG. 25D.
In addition, the sheet feeding member 803 may be pulled out of the apparatus body 801 each time the sheet tray 802 is pulled out. However, since the pulled-out length becomes long, and mechanical portions such as the gears and rolls of the sheet feeding member 803 become exposed, the risk of causing faulty operation to the sheet feeding member 803 due to such as an erroneous operation by the user becomes high.
Accordingly, from the viewpoint of preventing such trouble, as shown in FIG. 25B, movement restricting member 805 is preferably provided for temporarily restricting the movement, in a pulling-out direction, of the sheet tray 802 at a position where the sheet tray 802 is pulled out of the apparatus body 801 and where the sheet feeding member 803 is accommodated in the apparatus body 801.
It should be noted that when the sheet feeding member 803 is to be pulled out of the apparatus body 801, it suffices if the sheet feeding member 803 may be pulled out after unlatching the movement restricting member 805.